A 40-minute layover at Amsterdam Schiphol (AMS) is technically possible but extremely risky, especially in 2026. Schiphol is a "one-terminal" airport, meaning all gates are connected, which makes transfers faster than at airports like Heathrow. However, it is also massive, and walking from a "B" pier to an "H" pier can take 20–25 minutes at a brisk pace. A 40-minute connection only works if: 1) Both your flights are within the Schengen Zone (no passport control), 2) Your first flight lands exactly on time, and 3) You are an experienced, fast-moving traveler with only a carry-on. If you are arriving from a non-Schengen country (like the U.S. or UK), you must pass through passport control, which can have wait times of 15 to 45 minutes, making a 40-minute layover essentially impossible. Airlines like KLM often sell these "minimum connection time" tickets, but they are stressful. In 2026, most travelers are advised to book at least a 75 to 90-minute layover to account for potential flight delays and the sheer size of the airport, ensuring you don't spend your vacation sprinting through the terminal.